It is often necessary or desirable to deliver particulate material in accurate, measured amounts into containers. For example, a high degree of accuracy in the delivery of particulate material is required when the particulate material is a medication. The term "particulate material" as used herein is intended to include powders or granular material, regardless of the particle size. However, this invention is particularly adapted for use with finely divided particulate material, such as powders.
One way to deliver particulate material is to utilize an apparatus which includes a rotatable turret having a series of openings which can be filled with the particulate material. The turret is rotated to bring the openings to a filling station where the powder is removed from the openings. Rotating turret devices are shown, for example, in Leong U.S. Pat. No. 4,177,941, Colburn U.S. Pat. No. 2,314,031, Hafner U.S. Pat. No. 4,528,848 and Anderson et al U.S. Pat. No. 1,416,156. Unfortunately, none of these devices provides the accuracy and speed desired especially for the delivery of relatively large volumes of various particulate materials, such as medications in powder form.
One desirable technique for transferring the particulate material from the openings to the container at the filling station is with a blast of gas, such as air, under pressure. This is troublesome, however, when the container to be filled is in the form of a bag which can be inflated by the air. The prior art does not deal with this container inflation problem. In addition, equipment that handles particulate materials, particularly powders, is difficult to keep clean because of the tendency of the finely divided material to get between the movable parts of the equipment.